7050铝合金试样尺寸对淬火后时效应力松弛率的影响
Effect of size of 7050 aluminum alloy sample on aging stress relaxation rate after quenching
陆绍良 1夏玉峰 1张文祥 1杨文彬 1滕海灏1
作者信息
- 1. 重庆大学材料科学与工程学院,重庆 400044;重庆大学先进模具智能制造重庆市重点实验室,重庆 400044
- 折叠
摘要
通过有限元仿真和实验验证方法,研究了7050铝合金在4 h和165 ℃条件下时效过程中不同倍数H形试样的应力松弛行为.结果表明,模拟结果与实验结果吻合性较好,误差在8.81％以内;尺寸效应主要通过几何特征和淬火应力对时效应力松弛率产生影响;在实验范围内,若不考虑初始应力的影响,试样的倍数对时效应力松弛率不构成影响.在实际淬火应力下,4、B、C、D和H点的应力松弛率随试样倍数增大呈对数增加,E、F和G点则在0.44倍试样时出现应力松弛率的极大值,主要原因是试样在0.2～1.5倍区间时淬火应力随试样尺寸发生变化,影响了应力松弛过程;当试样在1.5～5倍区间时,淬火应力趋于稳定,使得时效过程的应力松弛率趋于稳定,尺寸效应减弱.
Abstract
Stress relaxation behavior of H-shaped samples with different scales of 7050 aluminum alloy during aging at 165 ℃ for 4 h was studied through FEM simulation and experimental verification methods.The results show that the simulation results are in good agreement with the experiment results,and the error is within 8.81％.The size effect mainly affects the aging stress relaxation rate through geometric characteristics and quenching stress.Within the experimental range,if the influence of initial stress is not considered,the scale of the sample does not affect the aging stress relaxation rate.Under the actual quenching stress,the stress relaxation rates of A,B,C,D and H points increase logarithmically with the increase of sample scale.For E,F and G points,the maximum stress relaxation rate occurs in the sample with 0.44 scale.The main reason is that the quenching stress changes with the sample size when the sample is in the range of 0.2-1.5 scales,which affects the stress relaxation process.When the sample is in the range of 1.5-5 scales,the quenching stress tends to be stable,resulting in a stable stress relaxation rate during the aging process and a weakened size effect.
关键词
尺寸效应/7050铝合金/应力松弛/蠕变Key words
size effect/7050 aluminum/stress relaxation/creep引用本文复制引用
基金项目
国家重点研发计划(2022YFB3403700)
出版年
2024
NETL
NSTL
万方数据